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FIB TEM specimens manufactured by the
"lift-out" method provide a rapid means of
preparing an electron transparent
cross-section from a specific site of interest.
Instead of beginning with a thin bar of material
mounted on a grid, a relatively large bulk
sample can be inserted directly into the FIB
chamber and a specimen created straight
from the samples' surface. Two trenches are
milled on either side of the site of interest, the
area in the middle is thinned until it is electron
transparent, and then the cross-section is cut
free by the FIB. The specimen is then "lifted
out" by the use of an electrostatic probe,
which retrieves the free sample from its trench
and deposits it on a TEM grid that is made up
of copper covered with any one of a variety of
thin films. The "lift-out" technique lends itself well to analyzing
surface contaminants in bulk materials.
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